26 months off payments made

Twice before attempting to close my contract I've been to the Parow centre store , the assistant said after last payment in" October " the accnt can be closed, I then went again after last payment "October 5th" , new info came to light the accnt can only be closed after the 26th (no questions asked by me just thinking that's how the system works) when by to a different store zevenwacght to close the account, assistant said everything is settled your sim is made to prepaid. NOVEMBER I start to receive sms from Telkom please pay your accnt ******x. I was confused thinking the accnt was then never closed I call online assistants as I do not always have the time to go to malls , online said system off but how ever Telkom bills in arrears . I then drew my bank statement in total I paid a contract over 26 months & as far as my understanding a contract is 24 months . I do understand 1st payment is connection fee but what about the other 25 months off payments how am I still liable for another payment? Up to date I receive treating "sms" clarity is needed here please explain what have I paid for 25 months . Why don't telkom call customers why sms with threats.